Why are spiders scary? © Getty Images

Why are spiders scary?

Arachnophobia could be an evolutionary or a cultural aversion - unfortunately, not knowing makes it difficult to get to the bottom of the fear.

Asked by: Tanya Sebastian, by email

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One idea is that in our evolutionary past we were surrounded by spiders that were dangerously venomous and this favoured our ancestors, who would run a mile when something scuttled along the skirting board. The problem with this theory is that arachnophobia is much more common in Europe than in Africa or South America. An alternative hypothesis is that spiders mistakenly became associated with disease in the Middle Ages – particularly with the Black Death. This led to a cultural aversion to spiders, which has been handed down through the generations ever since.


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